Guard Ben Hamilton suffered a "serious" concussion Sunday against the Raiders and is out for the season.

AP

DE Red Bryant injured a knee against the Raiders.

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Sunday

N.Y. Giants @ Seahawks, 1:05 p.m., Ch. 13

The Seahawks begin Wednesday with three vacancies on their 53-man roster and two former Pro Bowlers available on the league's waiver wire.

Just don't spend the day expecting the arrival of receiver Randy Moss or linebacker Shawne Merriman. Indications were the Seahawks weren't interested in acquiring either.

But Seattle does have bodies to add after placing defensive end Red Bryant and guard Ben Hamilton on injured reserve, ending their seasons. The Seahawks also released fullback Quinton Ganther and cornerback Nate Ness, each of whom started Sunday's game at Oakland.

Seattle announced the addition of one player Tuesday: Frank Okam, a defensive lineman drafted by Houston in 2008 and released last month. He is 350 pounds, the kind of guy who fits the mold of the larger linemen the Seahawks have sought. He is the 236th transaction since Pete Carroll became coach. Okam was signed to a two-year contract.

The Seahawks also took a look at veteran Hollis Thomas, who was in Seattle for a workout. Nothing appeared imminent.

The Seahawks also hosted workouts for Chris White, an offensive lineman who previously played with the Texans, and Jay Richardson, a defensive lineman who has played with the Raiders.

Those changes are a sign of just how much Seattle was hurting after Sunday's loss in Oakland. Bryant suffered an injury to his right knee in the second quarter, an injury Carroll had previously intimated could be season-ending. Bryant, a third-year player, was thriving after being moved from tackle to defensive end in the offseason. At 320 pounds, he was a key component in Seattle's shift to a larger defensive front. Kentwan Balmer will step into the starting role there.

Okam will provide depth in the middle. Defensive tackle Brandon Mebane could return this week after missing the past three games with a calf injury, but Colin Cole's status will be a question after he left Sunday's game with a sprained ankle.

Seattle needs alternatives along the offensive line, too. Hamilton suffered a concussion in the first quarter of Sunday's game, an injury Carroll referred to as significant. He was replaced by Chester Pitts, who played for the first time since September 2009, completing his comeback from microfracture surgery.

That change is one the Seahawks had moved toward the past month, Carroll hoping to get Pitts back earlier to solidify the left side of the line.

Left tackle remains a question. Carroll expressed hope rookie Russell Okung would be ready to practice Wednesday, just 10 days after suffering a second ankle injury in three months. Tyler Polumbus, his replacement, suffered a knee injury in the second half Sunday, and his status for this week is uncertain.

Ganther was cut for the second time this season, showing that Seattle expects Michael Robinson to be ready after he missed last week's game because of a hamstring injury.

Ness started in Oakland at right cornerback with Kelly Jennings out because of a hamstring injury and Walter Thurmond missing (concussion). Jennings and Thurmond are expected to practice Wednesday.